1. Field of the Invention
The present invention relates to a voice/data combination system and a method for managing a bandwidth in the system, more specifically, a voice/data combination system and a method for managing a bandwidth in the system in which a determination is made as to whether a bandwidth for real-time data service is available, and the bandwidth, when not available, is reserved, so that the real-time data service is performed when the bandwidth is available.
2. Description of the Related Art
With the widespread utilization of the Internet and a demand for a variety of services, an Internet protocol (IP) network has been significantly advanced in performance and service, which has resulted in an increasing demand for more services.
As one service demanded by customers, the IP network provides voice communication as well as data communication, and there is also a demand by customers for transmission service for a variety of voice services. Accordingly, a combination of voice over IP (VoIP) services by a terminal, such as a digital telephone and a single telephone, is necessary.
A voice/data combination system allows an existing terminal and an Internet terminal (e.g., a VoIP terminal) to communicate by transmission of data or voice over an IP network.
The voice/data combination system can provide VoIP service (i.e., Internet telephone service), Internet data service, and public switched telephone network (PSTN) telephone service.
For the VoIP service and the Internet data service, the voice/data combination system divides a bandwidth of a transmission medium (e.g., an optical cable) connected to the IP network in a virtual trunk way, and assigns the divided bandwidths to respective services.
Also, the voice/data combination system classifies services into real-time data service, such as VoIP service, and general data services.
The voice/data combination system performs traffic management by processing a real-time data service packet through assignment to Strict Priority Queuing (SPQ) and processing packets other than the real-time data service packet, i.e., a general data service packet, in a Weighted Round Robin (WRR) way.
A hypothetical representation of a typical traffic management in the voice/data combination system will now be described in greater details.
The voice/data combination system assigns a real-time data service packet to the SPQ and processes packets other than the real-time data service packet in the WRR way.
When a bandwidth for the SPQ is full, the voice/data combination system assigns a bandwidth required for the WRR for smooth processing of real-time data service and then performs the real-time data service. When the bandwidths for the SPQ and the WRR are full, the voice/data combination system drops an excessive packet using a traffic policy or a shaping scheme and retransmits the excessive packet when the bandwidth is available after a set time lapses. Therefore, this makes it difficult for the voice/data combination system to process the real-time data service in real time.
In other words, when the bandwidths assigned for the SPQ and the WRR are full, the voice/data combination system endeavors to equally process real-time data service, such as the VoIP service, and the general data service. Accordingly, traffic of the real-time data service, such as the VoIP service, is, undesirably, not processed in real time due to causes such as the occurrence of hop delay in the voice/data combination system.